ESR1 and viral infectious disease: Due to its unique mode of action, PROTACs technology has received great attention in the industry and has been applied to the possible treatment of cancers, immune disorders, viral infections, neurodegenerative diseases, etc. Arivinas, a clinical-stage biopharmaceutical company, recently disclosed the structures of the androgen receptor (AR) degrader ARV-110 and the estrogen-receptor (ER) degrader ARV-471 (Fig. 2b).3–5 The previously announced results indicate that ARV-110 is safe and effective for patients with metastatic castration-resistant prostate cancer(mCRPC).